Labor is accusing the Abbott government of leaning on the Fair Work Commission and attacking workers' conditions with a submission that asks for penalty rates to be balanced against other objectives of the system.
Parliamentary secretary Josh Frydenberg says the government simply wants awards to be less complex, and for the commission to take into account labour costs to business.
"If we are going to get a situation where people can take risks as entrepreneurs, can employ new people, then we need to have a wages market that is balanced, that is not down one end of the pendulum," he told Sky News on Wednesday.
The commission's full bench will begin hearings at midday (AEDT) as part of its review, which will allow it to vary minimum pay rates and conditions.
In a submission to the commission the Abbott government said awards needed to reflect a softening economic environment and labour market and the impact on employers.
"The commission must balance (penalty rates) against other elements of the objective when considering whether modern awards provide a fair and relevant minimum safety net," the submission says.
Opposition Leader Bill Shorten labelled the government submission "radical", saying millions of workers would be left worse off.
"They want to cut penalty rates and working conditions for Australian workers," he said in a statement.
Labor's workplace relations spokesman Brendan O'Connor said the government was using the review to "lean on" the commission.
"It's clear now that as far as Tony Abbott is concerned WorkChoices was not cremated - it had just been sedated until he was elected," he said.
A spokesman for Employment Minister Eric Abetz said it would be inappropriate to comment on the government's submission while the review was underway.
Greens workplace relations spokesman Adam Bandt said the government was attempting to wind back workers' pay and conditions.
"Australian workers need to know Tony Abbott is coming after their wages," he said.
